SiOx/C-Ag nanosheets derived from Zintl phase CaSi2 via a facile redox reaction for high performance lithium storage
Jie Xie, Lin Sun, Yanxiu Liu, Xinguo Xi, Ruoyu Chen, Zhong Jin
Abstract
As one of the high-capacity anodes in lithium-ion batteries (LIBs), silicon oxide (SiO x ) has attracted wide attention due to its high theoretical capacity, low cost, and proper working voltage. However, the huge volume change and the intrinsic poor conductivity of SiO x still hinder the practical applications. How to address the issues is the focus of current research. In this work, firstly, hydrogen passivated Si nanosheets (Si 6 H 6 ) were prepared from Zintl phase CaSi 2 , then, two-dimensional Ag nanoparticle modified SiO x /C nanocomposite was prepared via a facile complex redox reaction between Si 6 H 6 and AgNO 3 -aniline complexing agent. In this design, aniline was served as carbon sources, and Si 6 H 6 could be transformed to SiO x by AgNO 3 in mild solution condition. The obtained Ag modified SiO x /C (SiO x /C-Ag) electrode exhibited high specific capacity (550 mAh·g −1 at 0.6 A·g −1 ), superior rate, and cycling performance when served as anode for LIBs.